• 제목/요약/키워드: CPE

검색결과 267건 처리시간 0.022초

A Study on Multi-Layered EM Wave Absorber Using Natural Lacquer as a Binder

  • Choi, Dong-Han;Kim, Dong-Il;Choi, Chang-Mook;Li, Rui
    • 한국항해항만학회지
    • /
    • 제30권9호
    • /
    • pp.767-772
    • /
    • 2006
  • Generally, a silicone rubber and a chlorinated polyethylene(CPE) have been used as a binder for the development of high-performance composite EM(Electro Magnetic) wave absorbers. In this paper, the EM wave absorption performance of natural lacquer, which is newly proposed as a binder was investigated. The prepared MnZn ferrite EM wave absorbers are mixed with natural lacquer showed excellent EM wave absorption characteristics compared with MnZn ferrite EM wave absorbers which are mixed with the conventional binders. MnZn ferrite EM wave absorbers mixed with natural lacquer were prepared and their absorption ability was also investigated The EM wave absorbers are fabricated in different proportions of MnZn, or NiZn ferrite and natural lacquer, and their reflection coefficients are measured. The permittivity and permeability are calculated by using the measured reflection coefficients. The EM wave absorption abilities are calculated according to different thicknesses of the EM wave absorbers.

Development of Broadband Electromagnetic Wave Absorber for X-band Sensors in Double-layered Type Using Carbon

  • Choi, Chang-Mook;Kim, Dong-Il;Li, Rui;Choi, Dong-Han
    • 한국항해항만학회지
    • /
    • 제30권9호
    • /
    • pp.763-766
    • /
    • 2006
  • In this paper, the EM wave absorbers were designed and fabricated for X -band sensors using Carbon of dielectric material with CPE. The complex relative permittivity of samples is calculated by using measurement results of S-parameter. We simulated the double-layered type EM wave absorber with broad bandwidth using the measured complex relative permittivity by changing the thickness and layer, which was fabricated based on the simulated design The fabricated EM wave absorber consists of 1 mm first layer sheet facing metal with Carbon composition ratio 70 vol. % and 1.5 mm second layer sheet with Carbon composition ratio 60 vol. %. The measured results showed a good agreement to the simulated ones. It is found toot the optimized absorption ability of double-layered type EM wave absorber with thickness of 2.5 mm is higher than 10 dB from 7.8 GHz to 13.3 GHz.

A Study on Development of the EM Wave Absorber for ETC System

  • Park, Soo-Hoon;Kim, Dong-Il;Song, Young-Man;Yoon, Sang-Gil
    • Journal of electromagnetic engineering and science
    • /
    • 제8권2호
    • /
    • pp.70-75
    • /
    • 2008
  • In this paper, the EM wave absorber was designed and fabricated for countermeasure against EMI from a ceiling of a tollgate in ETC system. We fabricated several samples in different composition ratios of MnZn-ferrite, Carbon, and CPE(Chlorinated Polyethylene). Absorption abilities were simulated in accordance with different thicknesses of the prepared absorbers and changed complex relative permittivity and permeability according to composition ratio. The optimized mixing ratio of MnZn-ferrite, Carbon, and CPE was found as 40:15:45 wt.% by experiments and simulation. Then the EM wave absorber was fabricated and tested using the simulated data. As a result, the developed EM wave absorber has the thickness of 3.3 mm and absorption ability was more than 20 dB in the case of normal incidence and more than 11 dB for the incident angle from 15 to 45 degrees at 5.8 GHz. Therefore, it was confirmed that the newly developed absorber can be used for ETC system.

A Study on Smart Heat Radiating Sheet for Protecting Electronic Equipments on the Ship

  • Choi, Dong-Soo;Kim, Dong-Il;Kim, Doh-Yeol;Choi, Dong-Han;Kil, Gyung-Suk;Kim, Jae-Hwan
    • 한국항해항만학회지
    • /
    • 제35권7호
    • /
    • pp.569-573
    • /
    • 2011
  • In this paper, we developed a Smart Heat Radiating Sheet(SHRS) having the absorption ability of more than 15 dB, and thermal conduction rate more than 20 W/mk for port logistics RFID(Radio Frequency IDentification) system by using AMP(Amorphous Metal Powder) and shielding sheet. Firstly, the EM(Electro_Magnetic) wave absorber samples were fabricated by using AMP and CPE (Chlorinated Polyethylene) with different composition ratios of 80 : 20 wt.% and 85 : 15 wt.%, respectively. Secondly, we fabricated the Smart Heat Radiating Sheet using the shielding sheet to attach EM Wave Absorber. As a result, the Smart Heat Radiating Sheet with absorption ability of 16 dB at 433 MHz and thermal conduction rate is 24 W/mk has been developed with the composition ratio of Amorphous Metal Powder : CPE = 85 : 15 wt.% and thickness of 5.5 mm.

HEp-2 : VSV system을 이용한 인터페론 역가측정 연구 (Study of Interferon Assay by HEp-2 : VSV system)

  • 정인환;장욱;김현수;배종찬;이원영
    • 한국미생물·생명공학회지
    • /
    • 제13권1호
    • /
    • pp.27-31
    • /
    • 1985
  • WISH, FL 및 HEp-2 세포주중 분석용 세포주를 선정하기 위하여 VSV에 대한 sensitivity와 세포성장능을 조사하였다. 그 결과 HEp-2 세포주가 가장 유리한 것으로 판별되었으며, 이 세포주를 이용하여 초기 세포농도 $5{\times}10^5cells/ml$과 200TCI-$D_{50}$의 VSV활성을 사용하여 22~24hr내에 인터페론 역가 분석을 할 수 있는 방법을 개발하였으며, 이 방법에 대한 신뢰성을 조사한 결과 CPE-reading method와 유사한 신뢰도를 보여주었다.

  • PDF

제주지역의 akabane virus에 대한 역학조사 및 원인체 분리동정 (Isolation, identification and epidemiological study of akabane virus on Jeiu-do)

  • 강완철;김은주;현관종;전창익;김희석;이두식
    • 한국동물위생학회지
    • /
    • 제23권1호
    • /
    • pp.93-102
    • /
    • 2000
  • In this experiment, we studied the sero-positive rate of akabane virus in cattle from Jeju-do and analyzed the seroepidemiological features. In an analysis of 1,051 samples, the positive rate for neutralizing antibody in sera collected in nine regions on Jeju-do was 56.7%. The rate varied with the region. The positive rate was 69.6% in Aewol, 63.1% in Jeju city, 54.4% in Anduck, 51.0% in Hallim, 69.8% in Jocheun, 47.6% in Pyosun, 40% in Daejeong, 30.0% in Harkyung, 71.6% in Namwon, 24.5% in Sungsan, 133.,3% in Seokypo and 44.5% in Gujwa, respectively The rate also depended on the age of the cattle. The positive rate was 67.2% in calves 0- to 12-month old, 48.3% in cattle 13- to 24-month old, 65.4% in cattle 25- to 36-month old, and 65.4% in cattle more than ,B7 months old. To isolate the virus from calves with malformations including arthrogryposis and hydranencephaly, cerebral homogenates were inoculated into Vero cells, which were determined for cytopathic effect (CPE). Vero cells with CPE were examined for Akabane virus using an electron microscope (EM) and indirect immunofluorescent antibody test (EM). Typical virus particles with a width of 90-130nm and specific immunofluorescence in the cytoplasm of infected cells were sought for identification.

  • PDF

소와 돼지의 도체에서 Clostridium perfringens의 분리와 특성 (Isolation and characterization of Clostridium Perfringens on bovine and porcine carcass)

  • 채희선;김연하;김주영;김종화;김규현;최태석;신방우;이덕주;이정학
    • 한국동물위생학회지
    • /
    • 제29권2호
    • /
    • pp.97-102
    • /
    • 2006
  • A total of 1,848 samples was taken from bovine and porcine from January 2003 to November 2005. They were examined for the presence of Clostridiuml perfringens. The properties of the isolates were characterized for Gram staining, biochemical features and enterotoxin production. Forty-one strains (2.2%) of C perfringens were isolated from the 1,848 bovine and porcine carcass using selective media. 30 (3.2%) C perfringens were isolated from the 925 of bovine cacasses, and 11(1.2%) were isolated from the 923 of porcine cacasses. In TSC agar, all isolates showed lecithinase activity. The isolation rate was higher in spring and summer than in autumn and winter. Among 41 isolates, only 1 isolate detected the cpe gene in PCR. The PCR amplified band was observed 233 bp.

Square Wave Voltammetric Determination of Indole-3-acetic Acid Based on the Enhancement Effect of Anionic Surfactant at the Carbon Paste Electrode

  • Zhang, Sheng-Hui;Wu, Kang-Bing
    • Bulletin of the Korean Chemical Society
    • /
    • 제25권9호
    • /
    • pp.1321-1325
    • /
    • 2004
  • Sodium dodecyl sulfate (SDS), an anionic surfactant, can strongly adsorb at the surface of a carbon paste electrode (CPE) via the hydrophobic interaction. In pH 3.0 $Na_2HPO_4$-citric acid buffer (Mcllvaine buffer) and in the presence of SDS, the cationic indole-3-acetic acid (IAA, $pK_a$ = 4.75) was highly accumulated at the CPE surface through the electrostatic interaction between the negative-charged head group of SDS and cationic IAA, compared with that in the absence of SDS. Hence, the oxidation peak current of IAA increases greatly and the oxidation peak potential shifts towards more negative direction. The experimental parameters, such as pH, varieties of surfactants, concentration of SDS, and scan rate were optimized for IAA determination. The oxidation peak current is proportional to the concentration of IAA over the range from $5\;{\times}\;10^{-8}$ mol/L to $2\;{\times}\;10^{-6}$ mol/L. The detection limit is $2\;{\times}\;10^{-8}$ mol/L after 3 min of accumulation. This new voltammetric method was successfully used to detect IAA in some plant leaves.

Development of Broad-Band Electromagnetic Wave Absorber for X-band Sensors in Double-layered Type Using Carbon

  • Choi, Chang-Mook;Kim, Dong-Il;Choi, Dong-Han;Li, Rui
    • 한국항해항만학회:학술대회논문집
    • /
    • 한국항해항만학회 2006년도 International Symposium on GPS/GNSS Vol.1
    • /
    • pp.297-300
    • /
    • 2006
  • In this paper, the EM wave absorbers were designed and fabricated for X-band sensors using Carbon of dielectric material with CPE. The complex relative permittivity of samples is calculated by the measured S-parameter data. We simulated the double-layered type EM wave absorber with broad bandwidth using the measured complex relative permittivity by changing the thickness and layer, which was fabricated based on the simulated design. The fabricated EM wave absorber consist of 1mm first layer sheet facing metal with Carbon composition ratio 70 vol% and 1.5 mm second layer sheet with Carbon composition ratio 60 vol%. The comparisons of simulated and measured results are good agreement. As a result, the optimized absorption ability of double-layered type EM wave absorber with thickness of 2.5 mm is higher than 10 dB from 7.8 GHz to 13.3 GHz.

  • PDF